Özet:

Selective IgA deficiency sIgAD , using 5 mg/dl of serum IgA as the upper limitfor diagnosis and concomitant lack of secretory IgA, is the most common formof primary immunodeficiency. The pathogenesis of IgA deficiency is not known,although abnormalities in Ig class switching and the cytokines involved in isotype switching have been implicated. Common Variable Immunodeficiency CVID is a heterogenous group of B cell deficiency syndromes characterized byhypogammaglobulinemia, impaired antibody production and recurrent bacterialinfections. Defective T-cell activation may lead to an impairment in cognate T-Bcell interaction due to impaired expression of CD40 ligand and/or abnormalitiesin the production of T-cell-derived cytokines required for fully functional B-cellactivation, proliferation and/or differentiation which could indeed explain theimpairment in antibody production present in CVID patients. It has been foundthat cytokines are produced in low levels due to the decreased T cell functionwhich occurs as a result of the defect in CD40L expression in CVID patients

Anahtar Kelimeler: